We're looking at integrating our multiple datacenters' door lock / badging systems into a single system. We use HID proximity cards everywhere, so it needs to work with those (and hopefully some generic readers?). We're after something that is hierarchical, that has a centralized control point, that then pushes configs to the controllers that manage each facility. Of course it all needs to be IP enabled. We are very much interested in do-it-yourself, as the "integration and installation" quotes from the vendors we've seen tend to be astronomical.

Anybody have any experience on this that they'd like to share?

Thanks!
Randal